package day_2022_12_to_3.year2023;

import java.util.HashSet;
import java.util.Set;

/**
 * @author haomin
 * @date 2023/01/01 22:37
 **/
public class Day1_1_Num2351 {
    class Solution {
        public char repeatedCharacter(String s) {
            Set<Character> set = new HashSet<>();
            for(char c : s.toCharArray())
                if(!set.add(c)) return c;
            return ' ';
        }
    }
}